芍药醇对结肠炎小鼠Foxp3表达的影响及其机制研究

Effect and Mechanism of Paeoniflorin on the Expression of Foxp3 in Mice with Ulcerative Colitis

目的探究芍药醇对溃疡性结肠炎(UC)模型小鼠Foxp3表达影响及其可能的分子机制。方法将30只BALB/c小鼠分为空白对照组、UC模型组和芍药醇治疗组,每组10只,采用2%葡聚糖硫酸钠(DSS)口服2周建立溃疡性结肠炎小鼠模型,芍药醇治疗组用40mg/kg剂量芍药醇溶液灌胃治疗7天,末次给药24h后处死小鼠,取小鼠结肠观察组织形态变化,HE染色并进行组织病理学评分。流式细胞术检测小鼠外周血Treg和Th17细胞占总CD4+T细胞百分比,酶联免疫吸附法(ELISA)检测小鼠血清中IL-17、IL-6、IL-10和TGF-β水平,Western blot法和real-time PCR法检测小鼠结肠组织中Th17特异性转录因子(RORγt)和Treg特异性转录因子叉头蛋白P3(Foxp3)的蛋白和mRNA水平表达情况。结果与UC模型组比较,芍药醇治疗组小鼠溃疡性结肠炎明显好转;小鼠外周血清Th17细胞百分比减少(0.98%±0.24%),Treg细胞百分比相应增加(2.51%±0.25%),同时炎性因子IL-17(103.98±5.34pg/ml)、IL-6(89.65±5.34pg/ml)表达降低,IL-10(17.13±1.81pg/ml)和TGF-β(32.47±1.85pg/ml)水平明显升高;小鼠结肠组织中Foxp3 mRNA(1.01±0.25)和蛋白表达均增加,RORγt mRNA(1.71±0.11)和蛋白表达减少。结论芍药醇可以促进溃疡性结肠炎小鼠结肠组织中Foxp3表达,诱导Treg细胞分化生成,抑制Th17细胞分化,调节Th17/Treg细胞平衡,维持体内免疫平衡,减轻肠道炎性反应,从而起到缓解和治疗溃疡性结肠炎的作用。

Objective To explore the effect of paeoniflorin on the expression of Foxp3 in ulcerative colitis(UC)model mice and its internal mechanism.Methods Thirty BALB/c mice were divided into blank group,UC model group and paeoniflorin treatment group,10 mice in each group.The mouse model of ulcerative colitis was established by oral administration of 2%dextran sulfate sodium(DSS)for two weeks.The paeoniflorin treatment group was treated with paeoniflorin enema at a dose of 40mg/kg for 7 days.The mice were sacrificed 24 hours after the last administration.Mice colon were used to morphology observation,HE staining and histopathological scoring.The percentage of Treg and Th17 cells in total CD4+T cells in mice peripheral blood were detected by flow cytometry.The levels of IL-17,IL-6,IL-10 and TGF-βin serum were analyzed by enzyme-linked immunosorbent assay(ELISA).Western blot and real-time PCR were used to detect the expression of Th17-specific transcription factor(RORγt)and Treg-specific transcription factor prostaglandin P3(Foxp3)in mice colon tissues.Results Compared with the UC model group,the ulcerative colitis mice treated with paeoniflorin were significantly improved.The percentage of peripheral blood serum Th17 cells(0.98%±0.24%)was decreased while the percentage of Treg cells(2.51%±0.25%)was increased.Inflammatory factors like IL-17(103.98±5.34pg/ml),IL-6(89.65±5.34pg/ml)levels were decreased and IL-10(17.13±1.81pg/ml),TGF-β(32.47±1.85pg/ml)levels were significantly increased.Foxp3 mRNA(1.01±0.25)and protein expression were increased in colon tissue while RORγt mRNA(1.71±0.11)and protein expression were decreased.Conclusion Paeoniflorin can promote the expression of Foxp3 in colon tissue of ulcerative colitis mice,inducing the differentiation of Treg cells,inhibit the differentiation of Th17 cells,regulating the balance of Th17/Treg cells,maintaining the immune balance in the body,and reducing the intestinal inflammatory response,thereby relieving the role of treatment of ulcerative colitis.